Rescue and identification beacons that do not emit radio frequency signals are of particular interest in applications where radio frequency communications may be difficult to establish and maintain, where electronic interference or absorption prevents reliable communication, or where detection and interception of such signals may be problematic.
One way to meet these requirements is to use portions of the electromagnetic spectrum that include infrared light. However, there are a number of challenges associated with providing beacons of this type. Meeting size and weight constraints is critical to the success of such laser systems as these constraints impact the extent to which such devices are practically portable or hand-held. Additionally, such systems must be survivable in portable applications and must be capable of extended operation. Such requirements can significantly be perceived as having contradictory implications, with a desire for small size and light weight operation being contrary to the requirement of ruggedness which requires extras weight and size and the requirement of extended operation requiring significant power supplies which can add weight and volume again increasing challenges associated with providing for the desired ruggedness.
Further, systems that are highly complex or that require precise placement of and alignment of optical and electronic instruments tend to be more vulnerable to damage through incidental contact, thermal extremes, or other damage that may occur during operation. This again raises the requirements for the ruggedness of the system.
What is needed therefore is a small, portable, light weight, laser system that can generate appropriate signals without requiring precise placement of optical components.
Further, such a laser system should be designed to avoid unnecessary emission of non-radio frequencies in ways that might allow detection or interception of the emissions while allowing movement of the person.
Finally, the laser system must be easily used with any interactions with the system designed to enable, rapid confident use by field operatives who may be distracted, injured, under fire and who may be wearing gloves or other protective equipment.